Your colorized photo is great! Skin tones vary from person to person depending on whether they are in strong light or shade and colorizing skin is tricky. I think you got this one about right. Keep up the good work.

My father does digital photo restoration and colorization professionally.. Most times he goes pixel by pixel using an older version of Photoshop on a high-end Mac system. This is not a plug, but you can see here in an old wedding photo a sample of his work.